RTEVAdvances in Raman Spectroscopic Detection of Pesticide Residues: Focus on Substrate Innovations

The widespread use of pesticides in agriculture has significantly improved crop yields and pest control. However, the persistence of residual pesticides in food, soil, and water poses major risks to human health and the environment. Conventional detection methods, such as gas chromatography–mass spectrometry and liquid chromatography–mass spectrometry, provide high accuracy but are typically limited by complex sample preparation, long analysis times, and poor field applicability. In this context, Raman spectroscopy, particularly surface-enhanced Raman scattering (SERS), has emerged as a promising alternative for the rapid, sensitive, and nondestructive detection of pesticide residues. This review focuses on recent advances in the SERS-based detection of major pesticide residues (chlorpyrifos, thiram, and thiabendazole), which are frequently found in agricultural products and environmental samples. We highlight the fundamental principles of Raman scattering and SERS and introduce the mechanisms of signal enhancement via nanostructured substrates. Special emphasis is placed on the progressive development of high-performance SERS substrates, such as nanoparticle-decorated surfaces, hybrid bimetallic nanostructures, and 3D architectures, which significantly improve sensitivity, reproducibility, and stability. Finally, we discuss current challenges and future perspectives for translating SERS-based techniques into robust field-deployable systems for environmental monitoring and food safety assurance.